Changes in bacterial diversity, composition and interactions during the development of the seabird tick Ornithodoros maritimus (Argasidae)

2021

Article référencé dans le Web of Science WOS:000575755500001

Gomard Y., Flores O., Vittecoq M., Blanchon T., Toty Céline, Duron O., Mavingui P., Tortosa P., McCoy K. D.

Microbial Ecology, 2021, 81 (3), 770-783 ISSN 0095-3628

Characterising within-host microbial interactions is essential to understand the drivers that shape these interactions and their consequences for host ecology and evolution. Here, we examined the bacterial microbiota hosted by the seabird soft tickOrnithodoros maritimus(Argasidae) in order to uncover bacterial interactions within ticks and how these interactions change over tick development. Bacterial communities were characterised through next-generation sequencing of the V3-V4 hypervariable region of the bacterial 16S ribosomal RNA gene. Bacterial co-occurrence and co-exclusion were determined by analysing networks generated from the metagenomic data obtained at each life stage. Overall, the microbiota ofO. maritimuswas dominated by four bacterial genera, namelyCoxiella,Rickettsia,BrevibacteriumandArsenophonus, representing almost 60% of the reads. Bacterial diversity increased over tick development, and adult male ticks showed higher diversity than did adult female ticks. Bacterial networks showed that co-occurrence was more frequent than co-exclusion and highlighted substantial shifts across tick life stages; interaction networks changed from one stage to the next with a steady increase in the number of interactions through development. Although many bacterial interactions appeared unstable across life stages, some were maintained throughout development and were found in both sexes, such asCoxiellaandArsenophonus.Our data support the existence of a few stable interactions inO. maritimusticks, on top of which bacterial taxa accumulate from hosts and/or the environment during development. We propose that stable associations delineate core microbial interactions, which are likely to be responsible for key biological functions.

Limnologie biologique / Océanographie biologique [034] ; Entomologie médicale / Parasitologie / Virologie [052] ; Sciences du monde animal [080] ; Biotechnologies [084]

Fonds IRD [F B010079826]

fdi:010079826